This invention relates to a pressure relief valve, and more particularly to a pressure relief valve being of a metal rupture disc in the form of thin rupture members having a metal liner body with a weakened portion including, in the form of a scored pattern, where the metal liner is placed in juxtaposition with a bursting disc.
The present invention relates to safety pressure relief devices and, in particular, to rupture disc assemblies, including reverse buckling rupture discs, and also to methods of manufacturing such rupture discs and assemblies.
Rupture discs have been known in this art for many years. Normally, the rupture discs are manufactured to have a rupturable membrane to provide a safety mechanism to relieve excessive pressure within an over-pressurized system or vessel. The rupture disc and or rupture disc assemblies are typically placed within such a system or vessel so as to prevent the flow of a liquid or a gas through such a device until the rupture disc ruptures through excessive or over-pressure loads. Typically, rupture discs have a score pattern formed by cuts, machined or by other conventional methods into the dome portion of the disc to enable the disc to buckle and to burst when under excessive pressure.
Rupture discs having support rings providing cutting projections have been used, but are restricted in use, being capable of use with gases only and sometimes restricted in pressure range. Obviously, if a rupture disc assembly could be developed which had better operating characteristics, including the ability to be used within a gas and or liquid environment capable of low and or high burst pressures, all without reducing the economic viability of such discs, there could be a wider application for the use of rupture discs assemblies.
With the present invention, it has been found that by providing a rupture disc assembly having a support ring including a projection and a predetermined configuration for the continuous score line, in combination with a rupture disc, the disadvantages of using standard rupture discs with conventional support rings are overcome cost-wise and the combination of the present invention permits a wider range of application for varying liquid and gas usages, and varying burst pressures.
The present invention provides a rupture disc combination which permits the use of rupture disc members in association with a certain type of rupture disc assemblies which overcomes the disadvantages with rupture discs assemblies per se, and yet provides the advantages of certain features of known rupture discs.
It is therefore one aspect of the invention to provide in a rupture disc assembly having a support ring adapted to support a rupturable rupture disc member; said support ring including an aperture, an upper and lower surface and a continuous side surface, the improvement wherein the support ring includes contiguous cutting means about the inner peripheral wall, the cutting means comprising a plurality of adjacent arcuately contoured cutting means having an innermost surface of the arcuate contour spaced at a closer distance to said inner peripheral wall than outer ends of the arcuate contour.
In another aspect of the present invention there is provided in a rupture disc assembly having a support ring adapted to support a rupturable rupture disc member; the support ring including an aperture, an upper and lower surface and a continuous side surface, the improvement wherein the support ring includes engaging means for engaging a ruptured disc after rupture of the same, the engaging means comprising a projection extending upwardly from one of the surfaces of the support ring and extending inwardly of the surface over the aperture to thereby engage a displaced ruptured disc.
In another aspect of the present invention there is provided in a rupture disc assembly having a support ring adapted to support a rupturable rupture disc member; the support ring including an aperture, an upper and lower surface and a continuous side surface, the improvement wherein the support ring includes a contiguous cutting surface operatively associated with said projection, the cutting surface positioned on said inner peripheral portion on the support ring, the projection of the cutting surface having a generally clover-leaf configuration.
In various alternative embodiments, the device according to any of the above aspect, the disc further includes a dome having a pre-determined transition radius between the dome and the support ring.
In various alternative embodiments, the support ring includes a transition radius substantially corresponding to that of the disc.
In alternative versions, the support ring transition radius includes a diameter of the transition radius being smaller than the transition radius of the disc.
Desirably, in accordance with the present invention, there is provided in a rupture disc having a rupturable rupture member together with a support system including a support ring associated with the rupture disc, the support ring having a projection formed within the ring adapted to retain post burst disc material, the improvement wherein the rupture disc supporting ring comprises a predetermined continuous score line therein adapted to cut the rupture disc when the disc buckles at a predetermined pressure, the support ring with the continuous cut or score line being in operative association with the projection formed in the support ring.
It is therefore another aspect of the present invention to provide a bursting disc in combination with a support ring having a projection formed on one side ofthe ring in combination with a continuous score pattern is of a generally clover-leaf configuration.